The PINT database: a definitive compilation of absolute palaeomagnetic intensity determinations since 4 billion years ago

Abstract

SUMMARY Palaeomagnetic field intensity measurements, derived from rocks with ages that span geological time, provide a crucial constraint on the evolution of Earth’s deep interior and its magnetic environment. The palaeointensity database PINT has been updated to version v.8.0.0  and includes palaeointensity site-mean records spanning an interval from 50 ka to 4.2 Ga, compiling efforts from the palaeomagnetic community spanning from 1959 to the end of 2019. Nearly all site-mean palaeointensity records have been assessed using the qualitative reliability of palaeointensity (quality of palaeointensity, QPI) framework. This updated database brings together and harmonizes prior QPI and PINT compilation efforts into a unified database referred to as the PINT database, incorporating recent efforts since 2014 to assess QPI. The spatio-temporal distribution of the PINT database is analysed, revealing substantial biases towards young records (from the Brunhes chron) in the Northern hemisphere, and intervals with little to no palaeointensity data with a duration of 10s to 100s of millions of years in the Palaeozoic and Precambrian. General QPI compliance is characterized for the PINT database, which shows that the median QPI scores range from 2 to 3 (out of a total possible score of 10), with a positive trend towards increasing QPI scores in studies published after the year 2000. This illustrates an increasing community awareness of what is required to establish confidence in palaeointensity data and an increasing robustness of the large scale interpretations that can be made with these data. We additionally present a description of the long-term average dipole field strength with descriptive statistics for distinct intervals of Earth history.